Illumination devices for vehicles are typically attached to a housing support of the vehicle via three holder devices. A configuration having three holder device ensures that the illumination device can be attached to the vehicle support with no stress forces, particularly by means of screwing the illumination device in place. For example, holder devices are known from DE 295 09 925 U1 and from DE 10 2009 007 356 A1. These serve to align the illumination device in a longitudinal dimension of the vehicle, a transverse dimension of the vehicle, and also a vertical dimension of the vehicle. For this purpose, the holder device has a fastening clip which is connected to the housing of the illumination device, particularly molded onto the housing, a hollow bolt which is functionally connected to the fastening clip when the holder device is installed, and a fastening screw for fixing the hollow bolt on the housing support. The hollow bolt itself typically has an outer threading, and is typically screwed into a recess of the fastening clip.
The illumination device is aligned in three spatial dimensions of the holder device in two steps. The housing can be displaced axially and/or screwed into place by means of rotating the hollow bolt in a direction of installation of the hollow bolt. The fastening screw, having an outer diameter which is smaller than an inner diameter of an axial bore hole of the hollow bolt, can likewise be displaced in an alignment plane which is perpendicular to the direction of installation of the hollow bolt. In this case, the installation of the hollow bolt and the directional vectors of the alignment planes form three preferred spatial dimensions of the holder device.
For the purpose of further simplifying the attachment and the alignment of the illumination device in the housing, the holder devices are typically designed in such a manner and are attached to the housing such that the spatial dimensions of the holder devices correspond to the primary coordinates of the vehicle (the longitudinal dimension of the vehicle, the transverse dimension of the vehicle, and the vertical dimension of the vehicle). Although the attachment of the illumination device to the housing support by means of three holder devices has proven effective in principle, it can be necessary, particularly in the case of large and or especially heavy illumination devices, to have a configuration with more than three mounting points for the purpose of preventing vibrations.